One of the challenges in designing microaircraft (MAVs) is the fact that if their batteries are large enough to support the required range, they may not be able to carry them,media reported. However, scientists have developed an alternative, a solar-powered wing.
Created by a team of Chinese scientists, the Flexible Biobutterfly Wings (FBBW) are made of thin polymer sheets and coated with a nanocrystalmetal film on top. The prototype device is placed horizontally, with one end fixed to the holder and the other free to move.
When simulated sunlight hits FBBW, the temperature of the two materials increases, causing them to expand. However, since the FOLLOWING FEP (Ethylene Fluoride propylene) polymer expands more than the metal film at the top, the flap responds by curling inwards and up. Once fully curled, the bent top covers the rest of the FBBW to cool it down and thus flatten. In this way, the device curls up and down quickly and repeatedly, resulting in a beat that moves faster than the actual butterfly wings.
In a demonstration of the system, the researchers created a photodynamic rotating gyroscope, a toy sailboat that moves over the water by waving a sail, and a device that shoots electricity from the wings. Although no flying mini-robots equipped with FBBW have been built so far, this is one of the possible future uses of the technology.
Scientists recently published a paper on the study in the journal ACS Applied Materials and Interfaces.